A wild overestimation of parking demand at a mall in Manhattan has led to wasted space, reduced pedestrian accessibility, and undermining long term planning goals.

Basing pre-construction traffic projections on the average share of drivers at suburban big-box stores in the region, the project’s environmental impact statement estimated that 67 to 68 percent of shoppers would arrive by car and that the development would require nearly 1,200 parking spaces at peak periods. As a result, the East River Mall in East Harlem was constructed with 1,248 parking spaces, which is vastly more parking than needed to accommodate customers.

According to a paper by Kyle Gebhart, which won the student paper competition held by the American Planning Association’s Transportation Planning Division, despite subsidized parking rates the mall’s parking structure has a less than 40 percent occupancy rate even during peak periods. In order to accommodate shoppers, who developers expected would drive to the mall, they sacrificed pedestrian accessibility—narrowing adjacent sidewalks and widening streets. However, with only about 30 percent of shoppers coming by car and nearly 50 percent by foot, it’s clear that the predictions were way off.

According to an article by Noah Kazis in Streetsblog, the project’s lead developer, David Blumenfeld, traced the problem to the planning phase of the project. Because no big box stores had been built in such a dense urban area, they relied on data from similar developments in more suburban locations. Gebhart notes in his paper that while there may be other uses for some of the parking space, such as farmer’s markets or storage, at least some of it will likely go to provide parking for area residents—bringing more cars and car-dependency to New York. However, in the wake of the East River Mall’s development, some new big box stores have changed their tune with respect to parking – as noted by Kazis, a new Home Depot on 23rd Street has not attached parking at all.

Developers are not the only ones who pay the price when needlessly large parking areas are constructed. As Donald Shoup notes in The Trouble With Minimum Parking Requirements [pdf], parking can often drive up the cost of real estate dramatically, and when it is provided free or below market cost to drivers, the costs are simply passed on to others—in the case of retail, shoppers pay to subsidize parking through higher prices.